Biomolecular Structural Biology

methods for determining atomic structures

Scientists use a variety of experimental methods to discover the inner workings of biological molecules. These include X-ray crystallography, NMR spectroscopy, and electron microscopy. Each method has specific advantages for the exploration of biological molecules.

Geis Digital Archive (6)

Geis illustrated the structure of myoglobin, focusing on the folding pattern of the secondary structure of the protein. Unlike previous myoglobin Illustrations, this painting focuses on the tertiary structure of the molecule rather than the sequence or surface.

Geis illustrates the structure of bovine trypsin, an enzyme that breaks down proteins, which was first revealed by X-ray crystallography in 1971 and further explored in 1974 (Krieger et al., 1974). This illustration was originally published in Scientific American (Stroud, 1984). Trypsin is a protease, an enzyme that catalyzes cleavage of polypeptide chains (Stroud, 1984). Geis' sketch depicts the structure with a ball-and-stick model and displays the sidechains of aspartic acid (Asp102), histidine (His57), and serine (Ser195), known as the catalytic triad.

In Hendrickson and Teeter's molecular study in 1981, the crystal structure of crambin, a small seed storage protein, was determined based on the location of sulfur atoms in the protein. Using an artistic approach, Geis utilizes bright yellow shading and orange coloring to highlight the importance of these 6 sulfur atoms in this ball-and-stick representation. The backbone of the protein is depicted in blue.

The colored print depicts the structure of myohemerythrin, which was first revealed by X-ray crystallography in 1975 (Hendrickson et al., 1975) and further refined in 1987 (Sheriff et al., 1987). Geis's illustration depicts the tertiary structure of the protein, highlighting the four anti-parallel alpha-helices and the presence of mu-oxo-diiron (iron atoms in red and oxygen atom in pink) located within the core of the macromolecule (Myohemerythrin).

About PDB-101

PDB-101 helps teachers, students, and the general public explore the 3D world of proteins and nucleic acids. Learning about their diverse shapes and functions helps to understand all aspects of biomedicine and agriculture, from protein synthesis to health and disease to biological energy.

Why PDB-101? Researchers around the globe make these 3D structures freely available at the Protein Data Bank (PDB) archive. PDB-101 builds introductory materials to help beginners get started in the subject ("101", as in an entry level course) as well as resources for extended learning.

RCSB PDB (citation) is managed by two members of the Research Collaboratory for Structural Bioinformatics (RCSB):